Evaluating Zero-Drift Amplifier Performance

Analog applications are demanding better precision and drift performance due to improvements in data converter resolution and the economic drive to reduce or eliminate periodic calibration. Zero-drift amplifiers, which achieve microvolt-level accuracy and excellent low frequency noise, are the ideal choice for these high-sensitivity measurement systems. Many zero-drift op amps available on the market feature great specifications but the offset cancelation circuits used in their designs introduce signal artifacts that may significantly degrade performance. In many practical applications, especially those involving ADCs or even moderate levels of source impedance, these amplifiers will not achieve the accuracy suggested by their datasheets. The LTC2057 was designed to provide great zero-drift performance while suppressing artifacts to an extremely low level. These characteristics result in far better usability and real performance in the LTC2057 than in competitive amplifiers.